U.S. patent number 7,264,032 [Application Number 11/209,481] was granted by the patent office on 2007-09-04 for improper working position detection for tire mounting apparatus and method.
This patent grant is currently assigned to Schenck RoTec GmbH. Invention is credited to Werner Lehr, Andreas Peinelt.
United States Patent |
7,264,032 |
Peinelt , et al. |
September 4, 2007 |
**Please see images for:
( Certificate of Correction ) ** |
Improper working position detection for tire mounting apparatus and
method
Abstract
An apparatus for mounting a tire on a wheel rim includes a
mounting head with a tire bead deflector and a tire press-in
roller, and a drive that moves the mounting head toward, and
rotates the bead deflector and the press-in roller around, the
wheel rim. To avoid a damage-causing contact between the bead
deflector and the wheel rim, an arrangement for monitoring a
minimum spacing distance between the wheel rim and the mounting
head is arranged preferably on the bead deflector. If an improper
working position closer than the minimum spacing distance is
detected, the arrangement produces a signal that influences, e.g.
stops, the motion of the mounting head. The arrangement preferably
includes a contact member of a comparatively soft low-friction
material at a working end of the bead deflector. If the contact
member contacts the wheel rim, this actuates a piezoelectric
element to generate the required electrical signal.
Inventors: |
Peinelt; Andreas (Pfungstadt,
DE), Lehr; Werner (Modautal, DE) |
Assignee: |
Schenck RoTec GmbH (Darmstadt,
DE)
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Family
ID: |
35427879 |
Appl.
No.: |
11/209,481 |
Filed: |
August 22, 2005 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20060037712 A1 |
Feb 23, 2006 |
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Foreign Application Priority Data
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Aug 23, 2004 [DE] |
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10 2004 040 866 |
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Current U.S.
Class: |
157/1.22;
157/1.2; 157/1.21; 157/1.26 |
Current CPC
Class: |
B60C
25/132 (20130101) |
Current International
Class: |
B60C
25/135 (20060101); B60C 25/12 (20060101); B60C
25/122 (20060101); B60C 25/132 (20060101) |
Field of
Search: |
;157/1.1-1.33,1.44,14 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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28 29 936 |
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Jan 1980 |
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DE |
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696 11 143 |
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Jul 2003 |
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DE |
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102 22 164 |
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Oct 2003 |
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DE |
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0 767 098 |
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Jul 2003 |
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EP |
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06270619 |
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Sep 1994 |
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JP |
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Other References
" Balancing and Diagnostic Systems", 2002 Catalog RA 1020e of
Company Schenck RoTec GmbH, Landwehrstr. 55, D-64293 Darmstadt,
Germany, pp. 116 to 117 (2002). cited by other.
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Primary Examiner: Hail, III; Joseph J.
Assistant Examiner: Muller; Bryan R.
Attorney, Agent or Firm: Fasse; W. F. Fasse; W. G.
Claims
What is claimed is:
1. An apparatus for mounting a tire on a wheel rim a of a vehicle
wheel, comprising: a wheel rim support adapted to support the wheel
rim; a tire mounting head including a tire bead deflector adapted
to deflect a tire bead of the tire around a wheel rim flange of the
wheel rim, and a tire pressin roller adapted to press the tire bead
into a rim well of the wheel rim; a drive arrangement connected to
said tire mounting head and adapted to drive said tire mounting
head rotationally about a wheel rim axis of the wheel rim and
axially toward and away from the wheel rim along the wheel rim
axis; and arranged on said tire mounting head, a detector
arrangement adapted to detect an existence or non-existence of at
least a prescribed minimum spacing distance between said tire bead
deflector and the wheel rim, and signaling means for providing to
said drive arrangement a signal that is responsive to said
detecting and that influences the driving of said tire mounting
head by said drive arrangement; wherein said detector arrangement
comprises a contact member configured and arranged on said tire
bead deflector so as to come into contact with the wheel rim flange
in the event of an improper working position of said tire bead
deflector relative to the wheel rim, in which improper working
position said tire bead deflector fails to maintain at lease said
prescribed minimum spacing distance between said tire bead
deflector and the wheel rim; and wherein said contact member
protrudes by said prescribed minimum spacing distance from said
tire bead deflector toward the wheel rim flange so as to be
positioned to contact the wheel rim flange before any part of said
tire bead deflector contacts the wheel rim flange.
2. An apparatus for mounting a tire on a wheel rim of a vehicle
wheel, comprising: a wheel rim support adapted to support the wheel
rim; a tire bead deflector adapted to deflect a tire bead of the
tire around a wheel rim flange of the wheel rim; a drive
arrangement connected to said tire bead deflector and adapted to
drive said tire bead deflector rotationally about an axis and
axially in an axial direction along or parallel to said axis toward
and away from the wheel rim; a controller connected to said drive
arrangement and adapted to control an operation of said drive
arrangement; a contact member configured and arranged on said tire
bead deflector so as to come into contact with the wheel rim flange
in the event of an improper working position of said tire bead
deflector relative to the wheel rim, in which improper working
position said tire bead deflector fails to maintain at least a
prescribed minimum spacing distance between said tire bead
deflector and the wheel rim; and a signaling arrangement that is
connected to said contact member so as to be actuated thereby, and
that is connected for signal transmission to said controller,
wherein said signaling arrangement is adapted to emit and provide
to said controller a signal in response to said contact member
coming into contact with the wheel rim, and said controller is
adapted to control said drive arrangement in response to said
signal; wherein said contact member protrudes by said prescribed
minimum spacing distance from said tire bead deflector toward the
wheel rim flanges so as to be positioned to contact the wheel rim
flange before any part of said tire bead deflector contacts the
wheel rim flange.
3. The apparatus according to claim 2, wherein said contact member
is a mechanical contact member made of a low-friction plastic.
4. The apparatus according to claim 2, wherein said contact member
is configured and arranged so as to come into contact with the
wheel rim flange when said improper working position involves
either one or both of an improper radial position or an improper
axial position of said tire bead deflector relative to the wheel
rim.
5. The apparatus according to claim 4, wherein said contact member
is configured and arranged so that the contacting of said contact
member onto the wheel rim flange in said improper axial position
and in said improper radial position both cause an axial
displacement motion of said contact member in said axial
direction.
6. The apparatus according to claim 2, wherein said contact member
includes an a first contact surface that extends from said tire
bead deflector toward the wheel rim flange at an oblique angle
relative to said axis.
7. The apparatus according to claim 6, wherein said contact member
includes a second contact surface that extends perpendicular to
said axis and adjoins said first contact surface.
8. The apparatus according to claim 7, wherein said tire bead
deflector has an end surface that faces toward the wheel rim flange
and that has a surface configuration matching said first and second
contact surfaces of said contact member, wherein said surface
configuration includes a first surface section that extends
perpendicular to said axis and a second surface section that
extends at an oblique angle relative to said axis.
9. The apparatus according to claim 2, wherein said tire bead
deflector has an end surface that faces toward the wheel rim
flange, and said contact member is arranged on said end
surface.
10. The apparatus according to claim 9, wherein said end surface
includes a first surface section that extends perpendicular to said
axis and a second surface section that extends at an oblique angle
relative to said axis.
11. The apparatus according to claim 2, wherein said signaling
arrangement includes a wireless signal transmitter that is
connected for signal transmission to said controller by a wireless
transmission link and that is adapted to transmit said signal to
said controller in a wireless manner.
12. The apparatus according to claim 11, wherein said signaling
arrangement further includes a piezoelectric element as an energy
source that is adapted to provide electrical energy to operate said
wireless signal transmitter.
13. The apparatus according to claim 2, wherein said contact member
is connected by a pushrod to said signaling arrangement so that a
displacement of said contact member actuates said signaling
arrangement via said pushrod.
14. The apparatus according to claim 2, wherein said signaling
arrangement comprises a switching arrangement that is connected to
and mechanically actuable by a displacement of said contact member,
and an energy source that is connected to said switching
arrangement to be adapted to selectively produce said signal.
15. The apparatus according to claim 14, wherein said energy source
comprises a piezoelectric element adapted to generate an electrical
pulse as said signal.
16. A method of mounting a tire on a wheel rim of a vehicle wheel,
comprising the steps: a) providing an apparatus for mounting a tire
on a wheel rim of a vehicle wheel, said apparatus comprising: a
wheel rim support adapted to support the wheel rim; a tire mounting
head including a tire bead deflector adapted to deflect a tire bead
of the tire around a wheel rim flange of the wheel rim, and a tire
press-in roller adapted to press the tire bead into a rim well of
the wheel rim; a drive arrangement connected to said tire mounting
head and adapted to drive said tire mounting head rotationally
about a wheel rim axis of the wheel rim and axially toward and away
from the wheel rim along the wheel rim axle; and arranged on said
tire mounting head, a detector arrangement adapted to delect an
existence or non-existence of at least a prescribed minimum spacing
distance between said tire bead deflector and the wheel rim, and
signaling means for providing to said drive arrangement a signal
that is responsive to said detecting and that influences the
driving of said tire mounting head by said drive arrangement;
wherein said detector arrangement comprises a contact member
configured and arranged on said tire bead deflector so as to come
into contact with the wheel rim flange in the event of an improper
working position of said tire bead deflector relative to the wheel
rim, in which improper working position said tire bead deflector
fails to maintian at least said prescribed minimum spacing distance
between said tire bead deflector and the wheel rim; and wherein
said contact member protrudes by said prescribed minimum spacing
distance from said tire bead deflector toward the wheel rim flange
so as to be positioned to contact the wheel rim flange before any
part of said tire bead deflector contacts the wheel rim flange; b)
supporting and securely holding said wheel rim with said wheel rim
support; c) positioning said tire partly on said wheel rim; d)
using said drive arrangement, moving said tire mounting bead
including said tire bead deflector axially toward said wheel
rim.
17. The method according to claim 16, wherein said providing of
said signal comprises wirelessly transmitting said signal from said
signaling means to said drive arrangement that drives said moving
and said rotating in said steps c) and d).
18. The method according to claim 16, wherein said detecting means
comprises a contact member, wherein said signaling means comprises
a piezoelectric element, wherein said monitoring in said step f) is
performed with said contact member on said tire bead deflector that
contacts said wheel rim if said actual spacing distance falls below
said prescribed minimum spacing distance, and wherein said
producing of said signal comprises mechanically actuating said
piezoelectric element in response to a displacement of said contact
member due to said contact thereof with said wheel rim so that said
piezoelectric element produces electrical energy as said
signal.
19. An apparatus for mounting a tire on a wheel rim of a vehicle
wheel, comprising: a wheel rim support adapted to support the wheel
rim; a tire bead deflector adapted to deflect a tire bead of the
tire around a wheel rim flange of the wheel rim; a drive
arrangement connected to said tire bead deflector and adapted to
drive said tire bead deflector rotationally about an axis and
axially in an axial direction along or parallel to said axis toward
and away from the wheel rim; a controller connected to said drive
arrangement and adapted to control an operation of said drive
arrangement; a contact member configured and arranged on said tire
bead deflector so as to come into contact with the wheel rim flange
in the event of an improper working position of said tire bead
deflector relative to the wheel rim, in which improper working
position said tire bead deflector fails to maintain at least a
prescribed minimum spacing distance between said tire bead
deflector and the wheel rim; and a signaling arrangement that is
connected to said contact member so as to be actuated thereby, and
that is connected for signal transmission to said controller,
wherein said signaling arrangement is adapted to emit and provide
to said controller a signal in response to said contact member
coming into contact with the wheel rim, and said controller is
adapted to control said drive arrangement in response to said
signal; wherein said tire bead deflcctor has an end surface that
laces toward the wheel rim flange, and said contact member is
arranged on said end surface; and wherein said end surface has a
groove therein, and said contact member is movebly received partly
recessed in said groove.
20. An apparatus for mounting a tire on a wheel rim of a vehicle
wheel, comprising: a wheel rim support adapted to support the wheel
rim; a tire mounting head including a tire bead deflector adapted
to deflect a tire bead of the tire around a wheel rim flange of the
wheel rim, and a tire press-in roller adapted to press the tire
bead into a rim well of the wheel rim; a drive arrangement
connected to said tire mounting head and adapted to drive said tire
mounting head rotationally about a wheel rim axis of the wheel rim
and axially toward and away from the wheel rim along the wheel rim
axis; and arranged on said tire mounting head, a detector
arrangement adapted to detect an existence or non-existence of at
least a prescribed minimum spacing distance between said tire bead
deflector and the wheel rim, and signaling means for providing to
said drive arrangement a signal that is responsive to said
detecting and that influences the driving of said tire mounting
head by said drive arrangement; wherein said detector arrangement
comprises a contact member configured and arranged on said tire
bead deflector so as to come into contact with the wheel rim flange
in the event of an improper working position of said tire bead
deflector relative to the wheel rim, in which improper working
position said tire bead deflector fails to maintain at least said
prescribed minimum spacing distance between said tire bead
deflector and the wheel rim; wherein said tire bead deflector has
an end surface that faces toward the wheel rim flange, and said
contact member is arranged on said end surface; and wherein said
end surface has a groove therein, and said contact member is
movebly received partly recessed in said groove.
Description
PRIORITY CLAIM
This application is based on and claims the priority under 35
U.S.C. .sctn.119 of German Patent Application 10 2004 040 866.1,
filed on Aug. 23, 2004, the entire disclosure of which is
incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to a method and an apparatus for mounting a
tire onto a rim of a vehicle wheel, using a tire mounting head with
a bead deflector and a press-in roller as well as a drive for
rotating the mounting head about the wheel rim axis and for axially
moving the mounting head.
BACKGROUND INFORMATION
A tire mounting apparatus and method of the above mentioned general
type are known from the company catalog "Balancing and Diagnostic
Systems", 2002 Catalog RA 1020e of the company Schenck RoTec GmbH,
of Landwehrstrasse 55, D-64293 Darmstadt, Germany. At pages 116 and
117, the English version of the mentioned catalog discloses a tire
mounting or assembly machine for vehicle wheels, whereby the tire
is at first laid sloping obliquely onto the wheel rim of a vehicle
wheel to begin the tire mounting process. The lower tire bead of
the tire is partly located within the recessed deep well of the
rim, and partly protrudes outwardly above the upper rim flange. To
carry out the tire mounting process, the wheel rim is supported and
tightly held or clamped, and the tire mounting head (also called a
draw-down head or pull-on head) is lowered until the bead deflector
and the press-in or press-down roller contact the side of the tire.
Then the mounting head is rotated about the rim axis. The bead
deflector pushes against and along the tire bead to ensure that the
tire bead lies radially outwardly relative to the rim flange, and
then the following press-in roller axially presses the tire bead
downwardly into the deep recessed well of the wheel rim, while
simultaneously the lower tire bead is pressed into contact against
the lower rim flange. The mounting of the two tire beads onto the
rim can be carried out, as desired, either together in common in
one operation, or sequentially in two rotations of the mounting
head. The mounting head is adjustable to various different wheel
rim types, e.g. different rim diameters, rim widths, or rim
profiles or shapes. The adjustment can be achieved automatically in
connection with a preceding rim type recognition.
In practice, it has been found that the rim type recognition can
give incorrect rim type identifying data, for example due to a
malfunction or various type-recognition errors. Errors can also
arise due to interference in the transmission of the type
identifying data from the type recognition arrangement to the tire
mounting apparatus. Still further errors can arise during the
automatic or manual adjustment of the bead deflector and/or the
press-in roller, as well as the drive movements of the mounting
head. If the wheel rim is clamped on the rim support in an
uncentered or tilted manner, it gives rise to further positioning
errors.
The above mentioned errors can cause an improper working position
of the bead defector and/or the press-in roller relative to the
particular wheel rim being processed. In a worst case situation,
such improper working position can cause the bead deflector to
collide with, gouge into, or scrape along the wheel rim flange, or
excessively deflect the tire bead, and thereby damage the wheel rim
and/or the tire. Since the contact of the bead deflector with the
wheel rim flange occurs on the visible decorative side of wheel
rim, even the slightest visible damage leads to rejection of the
wheel rim, or damage of the tire leads to rejection of the mounted
tire-rim combination, in subsequent quality control. Furthermore,
any damage to the rim flange or the tire bead can make it
impossible to properly and successfully mount the tire on the rim.
The equipment itself, e.g. the bead deflector, can also become
damaged by improperly contacting and pressing against the rim
flange.
SUMMARY OF THE INVENTION
In view of the above, it is an object of the invention to improve a
tire mounting apparatus and method of the above mentioned general
type in such a manner so as to ensure the trouble free performance
of the tire mounting process, even for a succession of wheel rims
of different types or sizes. A further object of the invention is
to avoid damage to the tire, rim or equipment due to an improper
working position and especially contact between the bead deflector
and the wheel rim flange. The invention further aims to avoid or
overcome the disadvantages of the prior art, and to achieve
additional advantages, as apparent from the present specification.
The attainment of these objects is, however, not a required
limitation of the claimed invention.
The above objects have been achieved according to the invention in
an apparatus for mounting a tire on a wheel rim of a vehicle wheel,
comprising a wheel rim support, a tire mounting head and a drive
arrangement. The wheel rim support supports the wheel rim. The tire
mounting head includes a tire bead deflector that deflects a tire
bead of the tire around a wheel rim flange of the wheel rim, and a
tire press-in roller that presses the tire bead into a rim well of
the wheel rim. The drive arrangement is connected to the tire
mounting head and drives the tire mounting head rotationally about
a wheel rim axis of the wheel rim and axially toward and away from
the wheel rim along the wheel rim axis. According to the invention,
the apparatus further comprises detecting and signaling means,
arranged on the tire mounting head, for detecting an existence or
non-existence of at least a prescribed minimum spacing distance
between the tire mounting head and the wheel rim, and for providing
to the drive arrangement a signal that is responsive to the
detection and that influences the driving of the tire mounting head
by the drive arrangement.
The above objects have further been achieved according to the
invention in an apparatus for mounting a tire on a wheel rim of a
vehicle wheel, comprising a wheel rim support, a tire bead
deflector, a drive arrangement, a controller connected to the drive
arrangement to control the operation thereof, a contact member
configured and arranged on the tire bead deflector so as to come
into contact with the wheel rim flange in the event of an improper
working position of the tire bead deflector relative to the wheel
rim, and a signaling arrangement. In the improper working position,
the tire bead deflector fails to maintain at least a prescribed
minimum spacing distance between the tire bead deflector and the
wheel rim. The signaling arrangement is connected to and actuated
by the contact member, and is connected for signal transmission to
the controller. The signaling arrangement provides to the
controller a signal in response to the contact member coming into
contact with the wheel rim, and the controller controls the drive
arrangement in response to the signal.
Still further, the above objects have also been achieved according
to the invention in a method of mounting a tire on a vehicle wheel
rim, comprising steps of supporting and securely holding the wheel
rim, positioning the tire partly on the wheel rim, moving a tire
mounting head including a tire bead deflector axially toward the
wheel rim, rotating the tire mounting head to rotate the tire bead
deflector around a wheel rim flange of the wheel rim so that the
tire bead deflector deflects a tire bead of the tire around the
wheel rim flange, and pressing the tire bead into a rim well of the
wheel rim. During the steps of moving and rotating the tire
mounting head, the method further involves monitoring whether an
actual spacing distance between the tire mounting head and the
wheel rim is at least equal to a prescribed minimum spacing
distance. If the actual spacing distance falls below the prescribed
minimum spacing distance, then a signal is produced. In response to
the signal, the moving and/or the rotating of the tire mounting
head is influenced (for example stopped).
Advantageously, the invention provides that an improper working
position between the tire mounting head and the wheel rim possibly
arising before or even during the tire mounting process is detected
and produces a signal that suitably influences the tire mounting
process. For example, the tire mounting process is not started, or
the already-started tire mounting process is interrupted and the
apparatus is stopped, or the tire mounting head is repositioned
relative to the wheel rim. The improper working position of the
mounting head, and especially the bead deflector thereof, relative
to the wheel rim can arise from any of the above mentioned errors,
such as errors in the wheel rim type recognition or in the
transmission of the type identifying data, or errors in the
adjustment of the bead deflector or the press-in roller, or errors
in the support and clamping of the wheel rim. The invention
provides simple means to ensure that such in improper working
position does not lead to damage of the wheel rim or the tire, for
example because the further operation of the tire mounting
apparatus is immediately stopped if any such improper working
position is detected. Then, an operator of the apparatus can
determine the cause of the problem, and carry out any suitable
readjustment or repositioning (for example repositioning and
reclamping the wheel rim, or readjusting the position of the bead
deflector or the press-in roller especially regarding the axial
positions thereof). Thereafter the tire mounting process can be
started or continued, without having caused any damage to the tire
or the rim. Thereby the reject rate can be significantly
reduced.
It is also advantageous that the invention does not require complex
or costly additional devices, because the position or spacing
detection arrangement is preferably incorporated into the existing
bead deflector in a simple manner. An especially advantageous
further embodiment provides a wireless signal transmission from the
position detection arrangement of the bead deflector to the drive
arrangement or the controller thereof. Thereby a hard-wired cable
connection can be omitted, although an alternative embodiment uses
a hard-wired transmission of an electrical signal through an
electrical cable connection or of an optical signal through an
optical fiber connection. Such cable connections can be problematic
and subject to interference or breakdown in the actual production
process, especially if the cables must undergo rapid movements in
operation, in this case the axial and circular or rotational
movements of the tire mounting head. The preferred wireless
transmission according to the invention preferably is carried out
as a radio transmission (e.g. radio frequency RF transmission), but
alternatively may be carried out as an optical transmission (e.g.
an infrared IR transmission).
In a structurally simple preferred embodiment of the invention, a
suitable position detection element is incorporated into or
arranged on an end surface of the bead deflector that faces toward
or cooperates with the wheel rim flange. In a particularly simple
and robust embodiment, the position detection element is a contact
member or especially a switching feeler shoe of a switching
arrangement. When the switching shoe contacts the wheel rim flange,
the switching shoe is displaced through a switching displacement,
and in turn displaces a switching pushrod connected thereto, so
that the pushrod is slidingly displaced against a return spring
force, and in turn activates a switch that is preferably embodied
as a piezoelectric switch. This piezoelectric switch includes a
switching mechanism as well as a piezoelectric crystal element that
serves as an energy source. Since the piezoelectric effect is used
for supplying the necessary energy for the position detection
signal, it is not necessary to provide any external energy source
or any other internal energy source such as a primary or secondary
battery in the bead deflector. The piezoelectrically generated
energy can also be used for carrying out the wireless transmission
of the resulting signal, i.e. for powering the signal
transmitter.
A gentle handling or treatment of the tire is ensured by a further
embodiment in which the working end surface of the bead deflector
comprises a first surface section that extends perpendicularly to
the axis of the bead deflector, and a second surface section that
protrudes away obliquely at a slope or tilt angle from the first
surface section. Preferably, the second surface section is oriented
to slope obliquely away from the first surface section at an angle
of 45.degree..
The switching shoe of the position detection arrangement preferably
has a similar configuration as the working end surface of the bead
deflector, with two portions thereof respectively partially
recessed into a groove along the first surface section and the
second surface section of the working end surface of the bead
deflector. With such an embodiment, the wheel rim flange will
contact the obliquely sloping surface of the switching shoe for
either (or both) a radial improper working position and/or an axial
improper working position of the bead deflector relative to the
wheel rim. In other words, if the bead deflector is improperly
radially positioned, or improperly axially positioned, relative to
the wheel rim flange, then the rim flange will contact the sloping
surface of the switching shoe so as to cause an axial displacement
of the switching push rod in the axial direction and thereby cause
an operation of the switching arrangement, to generate a signal
indicative of the existence of the improper position in which the
prescribed minimum spacing distance is not being maintained. That
signal is transmitted to the controller and/or drive of the tire
mounting head, so as to stop or interrupt the motion of the
mounting head, or even to readjust the position of the mounting
head in an automatic responsive manner.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention may be clearly understood, it will now
be described in connection with an example embodiment, with
reference to the accompanying drawings, wherein:
FIG. 1 is a simplified schematic perspective view of an inventive
apparatus;
FIG. 2 is a partially sectioned side view of the bead deflector
with a position detector and signaling device of the inventive
apparatus of FIG. 1;
FIG. 3 is a partially sectioned front view of the bead deflector of
FIG. 2; and
FIG. 4 is an enlarged sectional detail view of the working end
portion of the bead deflector according to FIG. 2.
DETAILED DESCRIPTION OF A PREFERRED EXAMPLE EMBODIMENT AND OF THE
BEST MODE OF THE INVENTION
FIG. 1 schematically illustrates an apparatus for mounting a tire 1
onto a wheel rim 2 of a vehicle wheel. The tire mounting apparatus
is arranged and supported in a machine frame or tire mounting
station, of which the further components are not shown. The wheel
rim 2 is supported on a wheel support platform 9, which is
schematically indicated, and which includes any conventionally
known wheel holding or clamping device. The wheel rim 2 is thus
fixedly secured and held in the horizontal position on the wheel
support platform 9 by the wheel rim clamping device (not shown in
detail) thereof.
Above the wheel rim 2, the tire mounting or draw-down head 3 of the
tire mounting apparatus is movably arranged on the machine frame so
that the rotation axis of the tire mounting head 3 coincides with
the vertical wheel rim axis of the wheel rim 2. More particularly,
the mounting head 3 is connected to and supported by a drive
arrangement 13 so as to be rotatable by at least one rotation about
the vertical axis and to be displaceable in a stepless stroke
manner in the axial direction, as respectively indicated by the two
motion arrows. Thus, the drive arrangement 13 includes a rotational
drive mechanism and a linear stroke drive mechanism, which may, for
example, be operated electrically (e.g. an electric motor) and/or
via a suitable pressure medium (e.g. a hydraulic motor or
piston-cylinder device). Also, the drive arrangement 13 is
connected to or integrated with a control arrangement 7, which
controls the operation of the drive arrangement 13.
To carry out a tire mounting process, i.e. to press a respective
tire 1 onto a respective matching wheel rim 2, the drive 13 drives
the mounting head 3 vertically into a (nominally proper) axially
spaced position relative to the wheel rim 2, and then drives the
mounting head 3 rotationally to carry out at least one full
rotation, to mount the tire as will be explained below. In this
regard, the mounting head 3 must be properly positioned and
especially axially adjusted by the drive arrangement 13 under the
control of the control arrangement 7, dependent on the axial
position of the wheel rim side face of the respective wheel rim 2
positioned in the mounting station. Thus, if successive wheel rims
have different sizes, profiles, or types, then the mounting head 3
will have to be appropriately positioned to different axial
positions respectively proper for the respective different wheel
rims. For this purpose, the control arrangement 7 can receive
signals from a preceding type-recognition arrangement for
recognizing and identifying the different types or sizes of wheel
rims and/or tires. The control arrangement 7 can also receive
manual information through any suitable operator input arrangement,
such as a keyboard or adjustment switches, to identify the wheel
rim and tire type to be processed at any given time. The control
arrangement 7 then properly controls the drive arrangement 13 so as
to position the working components of the mounting head 3 properly
relative to the wheel rim 2 and the tire 1.
The working tools of the tire mounting head 3 include a tire bead
deflector or bead folder 4 and a tire press-in or press-down roller
5. The mounting head 3 may comprise a plurality of press-in
rollers. The bead deflector 4 and the press-in roller are secured
to an adapter part 8 of the mounting head 3 in such a manner so
that their respective positions in the radial direction are
adjustable for the purpose of accommodating or adapting to various
different wheel rim and tire diameters.
The press-in roller 5 is rotatably supported by a support arm 5a,
which in turn is releasably or removably secured to the adapter
part 8. The rotation axis of the press-in roller 5 extends
essentially perpendicularly to the wheel rim axis (and
correspondingly the rotation axis of the mounting head 3). Thus, as
the mounting head 3 rotates around the wheel rim axis, the press-in
roller 5 rolls along the sidewall of the tire 1, whereby the roller
5 presses the sidewall of the tire 1 down below the wheel rim
flange 2a as will be discussed further below. In this regard, the
press-in roller 5 is arranged behind or after the tire bead
deflector 4 in the rotation direction of the mounting head 3.
The tire bead deflector 4 is configured essentially cylindrically,
i.e. as a cylindrical rod, and comprises a working section 4a that
is to be pressed against the tire bead 6, a securing section 4b
that secures the bead deflector 4 to the adapter part 8, and a
middle section 4c extending between the working section 4a and the
securing section 4b. The working section 4a comprises an end
surface 10 that includes a first surface section 10a extending
along a plane normal or perpendicular to the axis of the bead
deflector 4, and a second surface section 10b extending obliquely
or sloping relative to the first surface section 10a, and
especially extending at a slope angle of about 45.degree. (e.g.
40.degree. to 50.degree.) relative to the axis, and sloping
outwardly away from the first surface section 10a. This
configuration can especially be seen in the side view of FIG. 2
(further in connection with the front view of FIG. 3).
A groove 11 extends linearly crosswise or transversely through the
middle of the end surface 10. In this regard, the groove 11 extends
from the circumference of the working section 4a of the bead
deflector 4 in the area of the first surface section 10a to shortly
before (i.e. displaced inwardly from) the circumference of the
working section 4a in the area of the second surface section 10b.
In other words, while the groove has an open end at the
circumference of the working section 4a on the first surface
section 10a, it does not penetrate through the circumference and
thus has a closed end at the circumference of the second surface
section 10b. This side of the circumferential surface 12 of the
bead deflector 4 (adjacent to the second surface section 10b) is
allocated to, faces toward and presses against the tire bead 6,
while the end surface 10 including the surface sections 10a and 10b
is allocated to and faces toward the wheel rim flange 2a (see FIG.
4).
The tire bead deflector 4 further comprises a signaling device or
arrangement 20, which generates or releases a signal that is
indicative of a relative position (or spacing) of the bead
deflector 4 with respect to the wheel rim flange 2a, and that is
provided to the control arrangement 7 and/or the drive arrangement
13 to influence the motion of the tire mounting head 3. The
signaling device 20 comprises a switching arrangement 21, an energy
source 22, and a signal transmitter 23, which is preferably a
wireless (e.g. RF or IR) transmitter, but may alternatively be a
hardwired transmitter. The signal transmitter 23 (preferably
wirelessly) transmits the signal to the drive arrangement 13 and/or
the control arrangement 7 for influencing, especially for stopping,
the drive arrangement. The significance of this will be discussed
further below. In this regard, the transmitter 23 is connected for
signal transmission to the drive arrangement 23 and/or the control
arrangement 7, e.g. by an RF wireless transmission link, an IR
wireless transmission link, a wire, an optical fiber, or other
signal transmission link.
The switching arrangement 21 comprises a switching feeler shoe or
foot 21a, a switching pushrod 21b connected to and actuated by the
switching shoe 21a, and a switch mechanism 21c that is acted on and
actuated by the switching pushrod 21b. The switching shoe 21a
consists of a material with a significantly lower hardness than the
material of the wheel rim 2, and with good sliding or anti-friction
characteristics. The terms anti-friction and low-friction mean
exhibiting a lower coefficient of friction than steel sliding
against steel. For example, the switching shoe 21a may be made of
any one of various low-friction plastic materials such as
polytetrafluoroethylene (PTFE). Thus, if the switching shoe 21a
comes into contact with the wheel rim 2 and particularly the wheel
rim flange 2a, then the switching shoe 21a can easily slide along
the rim flange 2a without causing any damage thereto. The switching
shoe 21a thereby forms a device or arrangement for detecting the
existence or non-existence of a minimum spacing distance between
the wheel rim 2 and the tire mounting head 3, particularly the bead
deflector 4 of the mounting head 3, whereby the prescribed minimum
spacing distance is given by the protrusion distance of the
switching shoe 21a beyond the end surface 10 of the bead deflector
4.
The switching shoe 21a is configured and dimensioned so as to fit
into the groove 11 provided in the end surface 10 of the bead
deflector 4. In this regard, a biasing spring, such as a
compression spring 21d, acting on the switching pushrod 21b biases
the switching shoe 21a to protrude outwardly from the groove 11,
but the switching shoe 21a can be pressed against the spring force
to be partly received or recessed in the groove 11. The switching
shoe 21a has a contour shape that is matched to the shape of the
end surface 10, i.e. including an angled profile having two shoe
portions extending at an oblique angle relative to one another
respectively along the first surface section 10a and the second
surface section 10b.
During the axial and/or radial positioning and motion of the
mounting head 3 and especially the bead deflector 4 relative to the
wheel rim 2, if the minimum spacing distance between the mounting
head 3 (especially the bead deflector 4 thereof) and the wheel rim
2 is no longer maintained, then the wheel rim flange 2a will
contact a sloping surface of the switching shoe 21a as shown in
FIG. 4. Such contact of the wheel rim flange 2a with the sloping
surface of the switching shoe 21a will arise for both improper
radial positions (as indicated by the arrow R in FIG. 4) as well as
improper axial positions (as indicated by the arrow A in FIG. 4) of
the wheel rim flange 2a relative to the bead deflector 4 (or vice
versa). In any event, either an improper radial positioning R or an
improper axial positioning A of the rim flange 2a contacting the
switching shoe 21a will result in an axial displacement of the
switching shoe 21a to be recessed into the groove 11, which in turn
causes an axial pushing displacement of the switching pushrod 21b
against the spring force of the biasing spring 21d upwardly as
indicated by the upward axial direction arrow at the top of FIG. 4.
Thus, through the arrangement of two end surface sections 10a and
10b that are tilted relative to one another, the first surface
section 10a (and its associated portion of the switching shoe) can
detect a height impact or deviation of the wheel rim 2, while the
second surface section 10b (and its associated portion of the
switching shoe) can detect an axial or radial impact or deviation
of the wheel rim 2, respectively onto the associated portions of
the switching shoe 21a.
As can be further understood in connection with FIG. 2, the upward
sliding displacement of the switching pushrod 21b due to the upward
recessing motion of the switching shoe 21a connected thereto is
transmitted by the switching pushrod 21b axially through the bead
deflector 4 and acts as a sliding displacement or stroke motion
onto the switch mechanism 21c. The switching motion of the switch
mechanism 21c in turn acts on a piezoelectric element provided as
the energy source 21. In response to this mechanical switching
actuation, the piezoelectric element or energy source 22 generates
an electric signal, e.g. an electrical pulse, which is then
transmitted by the transmitter 23 to the control arrangement 7
and/or the drive arrangement 13. In this regard, the electrical
energy emitted by the actuated piezoelectric element 22 can also be
used to power the transmitter 23, which is preferably a wireless
transmitter 23.
In the illustrated preferred example embodiment, the switch
mechanism 21c, the piezoelectric element or energy source 22, and
the transmitter 23 are all arranged in common in a housing at the
opposite or upper end surface of the bead deflector 4, i.e. at the
upper end surface of the securing section 4b opposite from the
working section 4a. Alternatively, however, the signaling device or
arrangement 20 can be arranged at any other suitable or desired
location of the mounting head 3. Also, as a further alternative, a
force-dependent signaling arrangement can be provided instead of a
displacement-dependent switching arrangement 21. As a further
alternative, the signaling arrangement can be based on, and can
release or trigger the transmission of a corresponding signal as a
result of an electrical contact measurement of an electrical
contact member or feeler contacting the wheel rim flange.
The process of mounting a tire 1 onto the wheel rim 2 of a vehicle
wheel using the inventive tire mounting apparatus will now be
described. First, the tire 1 is arranged over the wheel rim 2 in a
sloping or tilted manner so that the tire bead 6 is partly located
within the deep recessed well of the wheel rim 2 and partly
protrudes above the upper wheel rim flange 2a. To carry out the
tire mounting process, the wheel rim 2 is securely held or clamped
onto the wheel support platform 9. The tire mounting apparatus has
previously obtained appropriate data identifying the wheel rim
dimensions and possibly also the tire dimensions of the tire and
rim combination that is to be assembled or mounted. These data may
be provided, for example, from a preceding automatic
type-recognition arrangement, or from a manual input by an operator
of the apparatus. In response to these data, the control
arrangement 7 controls the drive arrangement 13 and any further
actuators as necessary to adjust the components of the mounting
head 3 to the proper tire and wheel dimensions, and then to lower
the mounting head 3 axially by a prescribed displacement distance
toward the wheel rim 2.
The tire mounting or assembling process begins in the area of the
tire 1 in which the tire bead 6 lies approximately at the height of
the wheel rim flange 2a. At the beginning of the mounting process,
the end surface 10 of the bead deflector 4 of the mounting head 3
is positioned at a certain prescribed minimum spacing distance away
from (e.g. above) the associated wheel rim flange 2a. Moreover, the
bead deflector 4 is positioned so that the axially further
protruding portion of the outer circumferential surface 12 thereof
(adjacent to the second surface section 10b) presses against the
tire bead 6 and thereby pushes the tire bead 6 radially outwardly
beyond and around the edge of the rim flange 2a. As the mounting
head 3 is rotated, the bead deflector 4 rotates around and along
the edge of the wheel rim flange 2a and thereby guides the tire
bead 6 radially outwardly along a circle around and over the edge
of the wheel rim flange 2a, as the following press-in roller 5 then
presses the tire bead 6 downwardly into the deep recessed well of
the wheel rim 2. The tire mounting or assembling process is
completed and ends when the mounting head 3 has carried out a
360.degree. rotation.
If the actual spacing distance between the end surface sections 10a
or 10b of the bead deflector 4 and the neighboring surface areas of
the wheel rim flange 2a falls below the prescribed minimum spacing
distance, during the initial lowering of the mounting head 3, i.e.
especially the bead deflector 4, toward the wheel rim 2, or during
the rotation of the mounting head 3 around the wheel rim axis, then
the edge of the wheel rim flange 2a will come into contact with the
switching shoe 21a, e.g. the obliquely sloping angular surface
thereof, before or without coming into contact with the end surface
10 of the bead deflector 4 itself.
As soon as such a contact between the wheel rim flange 2a and the
switching shoe 21a arises, the switching pushrod 21b is thereby
pushed upwardly, whereby the signaling device 20 is activated and
releases or generates a signal indicative of the detected improper
working position of the bead deflector 4 relative to the wheel rim
2. This signal is transmitted to the control arrangement 7 and/or
the drive arrangement 13, whereupon the lowering or the rotation of
the mounting head 3 is stopped or interrupted.
The worker who is operating or monitoring the tire mounting
apparatus can then determine and correct the cause of the improper
working position (e.g. by readjusting components as needed, or by
resetting the proper tire and wheel size data) before any damage
has been caused to the wheel rim and/or the tire. For example, if
the improper working position detection signal causes a stop of the
initial lowering motion of the mounting head, this can be
indicative of an error in the adjustment of the mounting head
components or in the detection of the wheel rim dimensions. On the
other hand, a signal-triggered stopping of the rotation process of
the mounting head can be caused by a faulty uncentered clamping of
the wheel rim 2 on the wheel support platform 9. As a further
alternative, the generated improper working position detection
signal can be used to automatically actuate a suitable corrective
readjustment of the mounting head or its individual components
relative to the wheel rim.
Although the invention has been described with reference to
specific example embodiments, it will be appreciated that it is
intended to cover all modifications and equivalents within the
scope of the appended claims. It should also be understood that the
present disclosure includes all possible combinations of any
individual features recited in any of the appended claims.
* * * * *